Catalytic apparatus



March 7, 1933.5- n Q 'JEGE'R n 1,900,382

l 1 cA'rALY'rIc APPARATUS l Filed Feb.. 25,v 192s 9 Sheets-sheet. 1

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' INVENTOR. -A/p/rons 0 Jaeger A TTORNEY A Ml'h 7 1933 A. o. JAEGER CATALYTIC APPARATUS` med rgb. 2s, 1928 9 sheets-sheet 5 lNVENToR. A/phons 0. Jaeger BY v l ATTORNEY. V

March 7, 1933. A. o. JAEGER CATALYTIC APPARATUS 9 sheets-sheet' 4 Filed Feb. 23. 1928 DJ M'd/ n .L .Arm-stl di d .Illlllll llll.

lI-III YC 4 a@ L ATTORNEY Matth 7, 1933. A. O JAEGER CATALYTIC .AJPARA'ILrs Filed Feb. 23, 1928 9 Sheets-Sheet' 5 INVENTOR. Alp/2ans 0 Jaeger A TTORNEY 40 m7 34 I 4l fi |||||||||||||||||||||||||1 w T, 4f MM ff W M46 Mallh 7, 1933. A o- JAEGER 1,900,382

cATALYTIc 'APPARATUS Filed Feb. 25, 1928 asheets-sheet e JJ M JJ Z A TTORNEY March 7, 1933. A o, JAEGER y 1,900,382

v CATALYTIC APPARATUS Filed Feb. 25, 1928 9 Sheets-Sheet 7 "59 "da" ,Z

IN V EN TOR.

ATTORNEY March 7, 1933. A. o. JAEGER CATALYTIC APPARATUS Filed Feb. 2s. 192s 9 Sheets-Sheet 8 INVENTOR. A/p/:ans 0. Jaeger l l A ATTORNEY.

March 7, 19.33. K A Q JAEGER 1,900,382

CATALYTIG APPARATUS Filed Feb. 23, 1928 9.SheetS-Sheet 9 v INVENTOR. Alphons 0. Jaeger BY ATTORNEY Patented 7, i933 UNITED STATES PATENT Vor-'FlcEv ALPHONS 0. JAEGER, .OF lGRAFTON, PENNSYLVANIA, ASSIGNOR T THE SELDEN COH- PANY, 0F PITTSBUBGHpPENNSYLVANIIA, A CORPORATION 0F DELAWARE CATALYTIC APPARATUS Application illed February 23, 1928. -Serial No. 256,189.

This invention relates to process and apparatus for catalytic reactions and more particularly to process and apparatus for catalytic reactions which are highly exothermic or, require avery delicate temperature control. Many reactions such as the catalytic oxidation of some organic compounds result 'in the production of large amounts of heat and tend to become uncontrollable for when the reaction temperature rises there is a tendency for the reactlon to proceed too far w1th great increases 1n exotherm so that one may considerythe reaction as in unstable equilibrium.

Many other reactions such as, for example, certain organic reductions may not be so strongly exothermic but require a very delicate temperature control for best results. In the past, reactions which are delicate or strongly exothermic have usually required Y the use of converters in which the catalyst s cooled'by means of liquid baths and the most effective type has usually been that in which the catalystis distributed in small zones, frequently tubes surrounded by a single bath.

In the past bath converters of two types have been used-those provided with baths which do not boil and those .which boil at or about reaction temperature. The former present many advantages in that the choice of bath liquid is very large and in the'case of converters used for high temperature reactions cheap baths, such as molten salt baths, molten lead baths, and the like, may be used. Converters provided with a non-boiling bath, however, have in many cases proved inadequate to control delicate or highly exothermic A reaction at high loadings with the desired degree of accuracy and have also frequently required rather careful and constant super,-

vision' to regulate the cooling. For thisreason boiling bath converters were used, in which, of course, the temperature regulation is entirely automatic and the heat capacity of the bath dueto the high latent heat of vaporization is so great that evensharp increases in exotherm can be satisfactorily controlled. This has rendered boiling bath converters preferable for many highly exo- K thermic reactions such as organlc oxldatlons and they present, of course, a great advantage of automatic temperature regulation and tremendous temperature controlling capacity.

Boiling bath converters, however, are subject to a number of very serious disadvantages especially for reactions which take-` place at high temperatures. For such reactions only a few liquids come into consideration, such as sulfur, mercury, mercury alloys and the like.v Mercury and its alloys have proven to be very satisfactory but they are very expensive and as the fumes of mercury are extremely poisonous extraordinary care must be used' in order to assure that all the joints are gas-tight. Sulfur, of course, is open to the lserious objection that it attacks most metals at high temperatures., v

uniform temperature control. In downiow converters', which are used most extensively at the present time, the most intense reaction takes place in the upper portion of the tubes and where a boiling liquid of low heating capacity is-used the top portions of the liql uid may be actively boilingV and the lower portions may berelatively cold, for with poor heat conductivity convective circulation is greatly decreased.

The present invention combines the advantages of both boiling and non-boiling types of converters, and does not possess the disadvantages of either. The converters of the present invention are provided with a bath which has a boiling point far above reaction temperatures. Elements of moderate size,

which are strongly cooled, and which may be 'metal rods of high heat conductivity extending beyond the bath, or compartments pro vided with liquids which either boil at'about reaction temperature or suciently near to it so that great temperature increases willstart therefore fully enjoyed by converters of they advantages of high cooling capacity, which are possible with boiling bath converters, are

present invention, and the inherent disadvantages are not present even where the cool-f ing elements contain liquids which boil at reaction temperature, for in the first place the ambunt of these liquids is very small comlpared with the total amount of bath and even when expensive do not greatly increase the cost of the bath. Bubble formation and knocking are alsounobjectionable, for the large quantity of non-boiling bath surroundv ing the catalyst chambers and theheat control elements equalizes yany local non-uniform coolin caused by the formation of bubbles in the oiling liquid compartments, and these latter need not be rigidly attached to the converter structure so that the shock` producgd by knocking need not be transmitted in its full severity to the converter structure,

orveven when the cooling elements arerigidly connected to the converter structure, as is knocking is correspondingly reduced in vio' desirable in some cases, the amount of liquid contained in them is relatively much] smaller than a vboiling bath in a converter, and the lence with the concomitant diminution of damage to the converter structure.

ln the converters of the present invention' the non-boiling bath, may be either purely a dowing heat transfer means to the cooling elements, either solid or liquid containing l consisting in liquid containing compartments g eo compartments boiling or non-boiling, or the cooling elements may be used only to compensate for fluctuations or variations in reaction exotherm. 'lihe nature 'ofthe final cooling, whether wholly by the cooling elements or partlyby them and partly by the non-boiling bath itself', will be chosenin ac# cordance with the requirements of the par- 'ticular installation. While the present invention includes as one of its most important embodlments the use of cooling elements distributed throughout or associated with the non-boillng bath, solid Aelements are Iof equal Aimportance in many cases, and are shown, for example, in Figs. l and 13 of the drawings.

Cooling elements, either solid or liquid, boillng or non-boiling, may also be in direct contact with the catalyst, as is shown for example in Figs. 8 and 9 of the drawings, but the invention does not include converts ers in which the whole of .the cooling elements are in direct contact with the catalyst itself. rlhe equalization of temperature throughout the non-boiling bath may result purely from the ordinary circulation ofthe latter due to dierence of heat evolved in various portions of the converter although in some of the. preferred embodiments of the invention, for example those shownin Figs. 2, 7, l1, and 13, positive circulation of the non-boiling bath may be employed and for many highly exothermic` reactions this method is of great importance and might be considered to constitutethe preferred embodiment of the4 present invention for reactions, requiring extremely powerful and sensitive temperature control. A portion of the cooling elements, or the vapor spaces thereo f when they are provided with boiling liquids, may be exposed to the air, to fresh incoming gases, or partly or Wholly to reactedgases, which are recirculated, as of course the principles of the present invention may be applied to converters operating with recirculation of part or all of the gas in order to provide an additional control in highly sensitive reactions and to increase the yield in many equilibrium reactions. lt is also advantageous in some cases to provide fora partly or wholly closed circuit gaseous cooling system to control the temperature of the cooling elements, and in the case of cooling elements provided with boiling liquids to effect condensation of the vapors. Liquid cooling means may of course be used instead of gas cooling as is shown in Fig. 7 l

of the drawings, and are applicable to solid cooling elements or to cooling elements filled with a non-boiling liquid as/well as to cooling elements provided with, boiling liquids as 7illustrated` in the figure. This cooling means may be of any suitable type and may, for example, constitute afl steam'boiler, the heat absorbed being utilized to raise steam. Such cooling means have been used in conjunction with boiling bath' converters and suitable construction will, oflpourseabe used by the skilled engineer. Obviously, of course, more than one method of condensing the vapors from the boiling liquids may be used.

While for most delicate react-ions it is desirable to utilize a boiling liquid which boils at a temperature suiiiciently below the reaction temperature so as to automatically maintain the desired temperature ofthe'nonboiling bath for some reactions which are I not so highly exothermic but which present some dangers of getting out of control it may be desirable to depend primarily on the cooling of the non-boiling bath as Ta primary cooling means, using the temperature regu lating effect of the boiling liquid compartthe bath containing a liquid that boils, say,

at 420. In such a case during normal operation the liquid in the separate compartments Will not boil and the non-boiling bath will control the reaction but if for any reason the reaction should get out of control and the temperature should rise sharply so that the bath became heatedv above 420 C. the liquid in the compartments would begin to boil andwould control further temperature increases, acting thus as a safety valve.l The present invention, of course, includes converters in Which the bath tempering means act either as normal temperature regulators or as emergency regulators or safety valves.

It should be clearly borne in mind that the present invention does not employ as its primary cooling means the principles of a boiling bath converter in which the boiling liquid is in heat exchanging relation with the contact mass. On the contrary in some modifications of the present invention the latent heat of vaporization of boiling liquids is not to control the temperature of the catalyst but to control the temperature of the bath, an entirely different method of control. This is perhaps most strongly brought out and most clearly illustrated in Figs. 7, 11 and 13 where the temperature regulation of the bath takes place outside of the converter. While in certain figures bf the drawingssom'eboiling liquids of the compartment are in direct heat exchanging `relation with the contact mass,

this effects only a secondary or minor cooling.

In the foregoing ,general description of the present invention the emphasis has been laid on exothermic reactions and this field presents perhaps the most striking incidents of the advantages of the temperature control 'possible by means of the present invention.

Itl should be clearly understood, however, that the invention is le ually applicable to reactions which are wea ly'exothermicor are endothermic and, therefore, require the application. of external heat. It is just as important to maintain a uniform temperature in many endothermic reactions as it -i's in exothermic reactions although perhaps this requirement is not as strikingly shown in the former class as the disastrous' results of lack of control in strongly exothermic reactions are somewhat more spectacular in their vio-v lence.

The present invention while it finds perhapsits most important field of usefulness in the control of organic oxidations is nevertheless generally applicable to all vapor phase catalyses both exothermic and endothermic involving organic and inorganic ,materials The following 11st of representative reactions of different classes is not intended in any sense to limit the scope of the invention but will serve as an indication of a few represenlv Converter systems embodying the principles of the present invention are applicablev to the most varied .types of organic oxidations, such as,

1. Reactions in which an intermediate oxidation product is produced. The oxidation of benzol, toluol, phenol, tar phenols or furfural and other compounds containing the cresol to salicylaldehyde and salicylic acid; toluol and the various halogen and nitro substituted toluols to the corresponding aldehydes and acids; xylenes, pseudocumene, mesitylene, paracymene and other derivatives to the corresponding aldehydes and acids; naphthalene to naphthaquinone, phthali anhydride and maleic acid; phthalic anhydride to maleic acid and fumarie acid; anthracene to anthraquinone; phenanthrene to phenanthraquinOne,diphenic acid, phthalic anhydride and maleic acid, acenaphthene to acenaphthylene, acenaphthaquinone, bisacenap-hthylidenedione, naphthaldehydic acid, naphthalic anhydride and hemimellitic acid; fluorene to fluorenone; eugenol and isoeugenol to vanillin and vanillic acid; methyl alcohol and methane to formaldehyde; ethyl alcohol to acetic acid; ethylene chlorhydrine to chloracetic acid and the like.

2. Reactions in which an undesired impurity is burned out, such as the purification of crude anthracenes of various degrees of impurity with total combustion of carbazole, dead oils and in some cases phenanthrene; purification of crude naphthalenes and crude mononuclear hydrocarbons, such as benzols and the like; purification of ammonia from coal tarwith the burning out of the organic impurities such as phenolic bodies present, etc.

3. Oxidation ofvmixtures-of organic compounds to desired intermediate products with removal of impurities such as the Aoxidation of crude anthracenes, phenanthrenes, and the like to intermediate products such as anthraquinone, phenanthraquinone, diphenic acid, phthalic anhydride, and the like with concomitant. removal'of carbazole and dead oils by total combustion; the oxidation of crude tar acids to maleic and fumarie acids with the combustion of certain impurities, etc.

Reductions and hydrogenations, such as, reducing nitro compounds, for example ni'- trobenzene, dinitrobenzene, nitrophenol, ni-

j''hydrogenatedll amines, the reduction of alde- V hyde'sand ketones toalcohols', such as benzaldehyde tof benzyl alcohol, acetaldehyde to ethyl alcohol, 4 crotonaldehyde to the. correspondingbu'tyl alcohol,and thevlike, the reduction of oxides 'of carbon tol methanol,

, methane, higher` alcohols 'and ketones or petroleum like'f products, the hydrogenationof aromatic compoundsto alicyclic Ecompounds such asy benzene to cyclohexane, naphthalene to tetraline or decaline, anthracene to hydrogenated anthracenes, phenol to cyclohexanol,

` :acetylene to ethylene and ethane', and.` the like, polybasic acids to innerl esters, such as phthalicl anhydride to phthalid', camphoric A acid to campholid, and the like, reduction of nitrogen containing heterocyclic compounds to aliphatic amines such as phridine to amylamine are also of importance.

In addition to reactions in which amore 'or lless homogeneous raw material is reduced certain mixtures of raw ;materials may be' effectively reduced with or Without the presence of additional.y reducing gases. rlhus for example, oxides of carbon may be reduced in the presence of the vapors of many organic compounds. For example, they may be reduced in the presence of aliphatic hydrocarbons, such as paratins, oleines, acetylenes, hydrocarbons having the :formula CIL 4 UH2' 6, etc. vHydrogen may be present or absent, and the class of products obtained,

such as mixtures of oxygenated compounds, or in many cases oils Which are predominately hydrocarbon in their nature, Will vary with the amount 4of the reacting ingredients and with the contact masses and reaction `conditions used, and it is anadvantage of the present invention that these novel combined reductions can be carried out in the desired direction with great effectiveness by the incorporation of suitable stabilizer promoters glyoxal, glyoxylic acid, oxalic acid, and the -r i like, may be used for vapor phase reductions 69g inthe presence of oxides of carbon and -hy- Ivdrogen. Oxidation products of trivalent a1- .cehols and divalentl isomeric alcohols may jals'o'be4 used, of course only where is possibleflto obtain the vapors of the compounds .without undesired decomposition.

' Leonesa pounds such' aldehyde alcohols, diketones,

triketones oxymethylene ketones, ketone aldehydes, ketone alcohols and the like, may also be combined with oxides of carbon and reduced in the presence ofthe contact mass described Jabove /to form many valuable products.

In addition to compounds of the aliphatic series which may be reduced together with oxides of carbon, various compounds of the allcyclic series, such as for example, alicyclic compounds, for instance, cycloparaflins, cycloolenes, cyclodiofines may be combined with oxides of carbon` and reduced. Examples of specic members of this class'are cyclohexane, cyclopentadiene, dicyclopentadiene, and the like. Of course alicyclic carbonyl compounds, such as cyclohexanol, cyclohexanone, etc., may be used, it being understood in this connection and throughout the specication that any compound containing the C() group, irrespective of Whether the oxygen is united to carbon with a single or a double bond, are included under the term carbonyl compounds.

Aromatic compounds, such as benzene hy-y drocarbons, naphthalenes, anthracenes, phenanthrenes, phenols, aromatic alcohols, aldehydes, ketones and acids maybe reduced in the presence of oxides of carbon and hydrogen, of course only insofar as the products are capableof volatilization Without undesired decomposition.

Heterocyclic compounds, such-as roducts y containing the furan'e nucleus, pyrro e bodies, pyrrolidines and the like, may be reduced together with oxides of carbon.

, The invention also may be applied to other vapor phase organic reactions such as the splitting o of carbon dioxide, for example, the transformation of polycarboxylic acids or their anhydrides intol monocarbexylic acids, as for instance/ the production of ben-1r zoic acid from phthalic anhydride. Dehydrations of all kinds, such as the production of ethers or unsaturated hydrocarbons from alcohols, for example, ethylene from ethyl alcohol, can be effectively carried out.

A. large number of reactions involving molecular associations such as polymerizations and condensations for example, the socalled ldolizations and crotonizations of aldehydes and the like constitute an important field of catalytic reactions for which the presy'ent invention is Well suited. Catalytic halogenations of organic compounds form another field 1n Whlch the present inventlon can 4be electively used. Catalytic esterifications form a category of reactions in which long and repeated contact with the catalyst is'. of-

importance and can be eiectivelyvcarried out by means ofl converters of the present invention.

` In the inorganic catalytic field synthesis of ammonia and oxidation of ammonia to nitrogen oxides are eiectively carried out 1n converter s stems embodying the temperature1 control eatures of the present invention and particularly converters provided with automatic gas-cooling for it is an advantage of' this type of construction that heat exchange elements do not have to be gastight which lends this type of converter construction for extremely h1 h pressure work suchas, for

example, hig pressure ammonia synthesis,-

organic reductions and hydrogenat1onsfor example, the reduction of oxides of carbon, etc. Hydrocyanic acid can also be catalytically produced from carbon monoxide and ammonia in converter systems ofthe present invention and the effective and simple temperature control which they assure is of iml-portance in improving yields and increasing outputs in this reaction.

Fig. 3 is a vertical section through a converter similar to Fig. 1,-provided with a con,-

tinuous circulation of reaction gases over the .vapor spaces of the liquid compartments;

Fig. 4`is a vertical section through a tubular converter of the general type shown in- Fig. 1 but provided with a closed circuit gaseous cooling system for the boiling liquid compartments.

Figs. 5 and 6 are detailed vertical sections through modified forms of .cooling elements;

Fig. 7 illustrates a converter ot the general design of Fig. 1, 'but providedwith -li uid cooling of the vapor spaces of the boi ingl li uid compartments; ig. 8 is a vertical section through' a .converter having a gaseous cooling circulation similar to that in Fig. 4 but being further provided with additional liquid compartments in direct contact withthe catalyst in the tubes; Fig. 9 isa vertical section through a convertexi similar in design'to that of Fig. 8 but 1 provided with recirculation of. reacted gases;

. Fig. 10 is a vertical section through a converter provided with closed circuit gaseous verterof the type shown in Fig. 11 but provided with a valved pipe 13 where a plural- .bottom piecef-and the lower tube sheet` control of the y.temperature of the bath 7 -is the cold or'cool reaction gases and serve 'to similar in its general design to that in Fig.

coolin system which also circulates any ,ya-

pors o the non-boiling bath formed;

Fig. 11 is a vertical section through a tubu-l lar converter provided with non-boiling bath and an external cooling compartment provided withv liquid chambers withgas cooling;

Fig. 12 is a horizontal section along the line of 12-12 of Fig.11; and

Fig. 13 is a vertical sectlon through avcon-i u vided with solid temperature equalizing means in the non-boiling bath.

Inl the construction shown in Fig. 1 the converter consists of a` shell 1, top piece 2, bottom piece 3, top and l'bottom tube sheets 4 3 'and' 5, and catalyst tubes 16.' A non-boiling bath 7 surrounds the "catalyst tubes andis provided with compartments 8 containing a liquid and extending through the tube sheet l 4. 'A solid metal temperature equalizing ele- 8.5

4 ment is also shown at 9 and may, of course, be interspersed with the liquid temperature means. The non-boiling bath compartment is provided with suitable vent pipes 10 and thermocouples are immersed in the boiling liquid of some of the compartments A8. Reaction gases enter the top piece`2 through the pipe 11 controlled by the valve 12 and proity of gases are to be intr'duced. The gases 95 are distributed by means of the ballies 14 and flow over the vapor spaces of the compartments 8, pass down through the catalyst tubes into the bottom space defined between the thence leaving through' the exhaust pipe 15. Cooling is 'primarily effected by the converter shell which may be air cooled and the final eiected by the liquids in the compartment 8 which may preferably boil at about reaction tempera-ture. The vapors in these compartments are in turn condensed by contact with heat up the latter to the desired reaction temno perature. It should be iclearlyunderstood that the drawings are purely diagrammatic in nature and do not show structural details,

such asfinsulatio'n and the like, which form nopart-of the present invention and which 1m are well known tothe skilled chemical engineer.

Fig. 2 illustrates a converter somewhat 1 provided with a non-boiling bath surrounding the catalyst tubes and containing compartments of'boiling or non-boiling iquid.

-LA central well 16 extends from near the bot-Ik tom orwthe non-boiling bath up through the top'piece of the converter. This well 1s provided with suitable openings 17 at its lower end and 18 at its upper end and rests on a bearing block 19. A screw propeller 2O turns in the well, the shaft 21 extending b eyond the converter, and forcesthe noli-boillao ing bath to circulate. The circulation may be in either'direction but since the tendency is uniformity of temperature throughout. The

converter is shown without directing baffles for the circulation of the non-boiling bath but where desired suitable directing bames may be incorporated if this is found to be desirable in order to enhance the uniformity of temperature control. v

Fig. 3 -illustrates al converter similar to Fig. 1 but provided with a recirculation of reactinggases before the latter pass through the catalyst, thus increasing the amount of gases'passing over the vapor spaces of the' boiling liquid compartments. rlhis recirculation consists in a pump 22 which forces gas through the pipe 23 controlled by the valve 24 into one side of the upper compartment of the converter, whence the gas flows over the vapor spaces of the compartment passing" out through the pipe 25, whence it can ow through the pipe 26 back to thepump.

. The gases may, however, be caused to flow through the heat exchanger 27, which is shown as of the ordinary tubular type. The proportion of gases iowing through the heat exchanger will be determined by the setting of the valves 28 and 29 in the pipe 25, thel valve 30 in the pipe 26, and the valve 3l in the branch pipe 32 which leads from the pipe 25' to the heat exchanger 27. Fresh gases enter as usual through the pipe 11.

Not only does this construction of Fig. 3

provide for and markedly enhance the cooling e'ect of the boiling cooling compartments but a very rthorough mixing of the reaction gases is made possible by the pumping around and this is desirable in many reactions.

In Fig.l 4 a converter of the general design of Fig. l is shown but is provided with a perforated partition 33 above the upper tube sheet 4 provided with catalyst charging holes closed by plugs 34. The tops of the boiling liquid compartments 8 extend through the partition 33, suitable 'care being taken to effect a tight joint. Reaction gasesenter the compartment defined between the compartment 33 and the upper tube sheet 4 through the pipe 35 and flow through the converter in lthe usual manner. Cooling of the vapor space of the compartment 8 is eected by directing a blast of cold gas over them. Gas isforced by the pump 36 through the pipe 37 into the itication is of importance.

pipe 38 with or without passing through the nned or corrugated pipes 39 and 40 which junction of the two coolers 39 and 40 to thed pipe 37 and is provided with 'a valve 46. This pipe also extends in the form of a T and gases from an lexternal source may be introduced therethrough, this introduction being controlled by the valve 47. A. similar introduction into the pipe 37 immediately after the ump discharge is ei'ected through the branc pipe 48 controlled by the valve 49 and valves 50 and 51 are mounted in the pipe 37 on each side of the joint where the pipe 45 enters. Pipe 52 connects the converter cooling space with the intake of the pump or blower 36. llt will be evident that the circulat-ing gases may be passed either through mic reactions which, however, require that the reaction gases enter the catalyst at a fairl high temperature and particularly a unibrm temperature. rlhis is readily possible by providing an entirely separate and independent cooling means for the boilin liquid compartments, which cooling means epends in no way on the amount or temperature of the reaction gases ilowingover the 'boiling liquid compartments. rlhe converter system is, of course, applicable to other types of reaction where the more positive and definite temperature control possible-in this mod- Solid rods or compartments containing non-boiling liquids may also replace the boiling liquid compartments 8.

Figs. 5 and 6 illustrate modified types of well suited for carrying out highly exotherliquid compartments. In the modification shown in Fig. 5 an inner circulating tube 53 is provided, preferably carrying perforations at its lower end. A rapid circulation of the liquid is thereby eiected which tends to prevent vapor locking or uneven ebullition. Fig. 6 illustrates a boiling liquid compartment provided with a jacket 54 provided with a non-boiling liquid 55. V This type of compartment will not boil in response to mQmentary fluctuations of temperature of cooling effect of the boiling liquids is used primarily as a safety valve. Other modifications of boiling ornon-boiling liquid compartmentconstruction are,

also well suited for endothermic reactions ofcourse, includas it is, of course, readlly feasible to extered- "andfwill'be clear to the skilled engineer. nally or internally heat the chamber 56, the

7 illustratesa-converter provided with bath being maintained at a uniform tempera HOB-boiling'bath and. with an/adjacentcoolature by boiling the liquid in tubes 8 and the Ling chamber l, 56 connected to theconverter hot bath is then circulated through passages 57 and '58 respectively, 4 former` entering'at the upper level of the reaction taking place therein. In such acase, .v non-boilingbath and' the latter approximate' of course,

through the conthe verter where it is .cooled b the endothermic the d1rection of circulation should ly'at the bottom.' The non-boiling bath freenaturally be reversed as will be self-evident -ly C'ICllla'teS tllIOllgll the. Chamber 56, being' to the skilled engineer'and such slight modiirnpelled bythe propeller 59 -driven by` the fication of construction adapting the invenmo'tor 60. The circulationis,7of course, from tion for use in endothermic reactions will the chamber 56 through the pa'ssage 58 into be made in any particular installation and thel COHVCIG and back tllIOllgll the passage are, of course, included Within the scope of 57. The parts of the` converter, of course, the invention, A bear the same reference numerals as in the Fig. 8'illustrates a converter substantially foregoing-figures. In the chamber 56 are the same as that shown in Fig. 4, similar IOVided COOliIlg elements 8 Which are SllOWIl parts bearing like reference characters, eX- as filled with a boiling-liquid and connected eept that it is provided with some of the at their upper ends t0 tank 61 in Which the temperature regulating elements 64 passing boilingliquid is maintained at a mOre 0r directly into the catalyst tubes, and being in --grammatically but in practice it ma less definite level. 'FI'OIn the VapOl Space 0f direct heat exchanging contact with the cata-fthis tank the vapors are caused to flow into lyet7 thereby providing an additional conthe condenser 62 cooled by water from a steam trol of reaction boiler 63, in which condenser they are con- Fig, 9 Shows a Converter of the design of densed producing steam 'and thecondensate that 0f Fig- 8 but provided with partial relOWS back ntO the tank 61- This COIISFIUP- circulation of the reacted gases. The recirtion assures a uniform distribution o f llquld enlation is effected by Causing n, Smaller or to all of the tubes 8 but where deslled, 0f larger amount of the gases from the exhaust cogrse, aliquidlevel can be maintained 1n the pipe 6 to pees throu h the branch pipe 65 tu es. diagrammatically and any. suitable construcfresh tion may be used. pipe thence flow to the suction of the The arrangement of lflg- 7 1S l11gl11y efblower 68 which forces the gases into the fective as positive forcedcirculation of nonpipe 69 leading to the intake of the conboiling bath iS obtainedV and the tfnlpelatllle verter. Additional fresh gases may be introis regulated to a nicety by the bo1l1ng of the duced directly into the pipe 69 through the 111 tl'levCOOllIlg elements laltl Valve 0r through the Valved 71, The also do not have t0 be InOllnted directly 111 proportionate amount of recirculation may the converter Which greatly simplifies .lts be regulated by suitable adjustment of the mechanicalgconst'ruction and the ease wlth Valve 72 in pipe 65 or the valve 73 in the which catalysts can be charged into it. Such discharge of the blower, The operation of a construction pOSSeSSeS many advantages the gas cooling circuit is, of course, identical from an operating standpoint but is, of with that Shown in Figs. 4 and 8, course, less compact than some of the other Fig, 10 illustrates a, converter provided designs. The converter is shown purely diawith closed circuit gas cooling means operatbe fleing as in Figs. 8 and 9 but instead of the sirable to provide suitable bailin m order cooling. gases flowing/over the extended coolt0 distribute the 'lOW 0f l10n-b0llng bath ing elements -a converter construction is used over the 'various tubes to assure uniform in which the cooling elements do not extend cooling throughout the converter. Of course, through the Ipartition 4 and, therefore, the where desired, more than one external coolgas blast flows under the latter in the vapor ing zone may be provided wherever the adspace above the non-boiling bath. This pervan'tage of somewhat vgreater uniformity of mits a more compact construction and the cooling justifies the additional complication. cooling elements do not extend above the par- The forced mechanical circulation, of course, tition 4 and therefore do not interfere with may be dispensed with but only at a considfilling in catalysts. The reaction gases are .erable sacrifice of coolin uniformity as the also not brought into contact with the cooling 69" tto vprovide adequateand. uniform cooling at a temperature not differing greatly from normal 'convection .circu ation is too slight elements and, therefore, enter the catalysts h th very highly exothermic reactions or rethe entrance temperature. This is an advanf'tions'. where considerable fluctuations of tage in some cases where it is undesirable to exetherm are unavoidable. heat up the reaction gases before they con- The type of converter shown in Fig. 7 is tact with the catalyst. In a construction as The Steam boiler iS SllOWIl merely into the mixing cham er 66 where additional gases may be introduced through the n 6 i in Fig. it should be borne in mind, of course, that the gas in the cooling circuit contacts with the surface ofthe non-boiling bath andcare should, therefore, be taken that. the bath is not attacked thereby by suitably choosing the bath and gases used.

Figs. 11 and 12 illustrate a converter operating precisely as in Fig. 7, like parts, of

. in this manner and be suitably preheated by the heating elements 8. These latter may, of course, be solid or contain liquids, either boiling or nonboiling, the type chosen depending onI the reaction to be controlled.

This construction is very economical of heat.

and may advantageously be used in reactions in which it is necessary .to heat up the reaction gases to a relatively high temperature before the latter pass through the contact mass.

Fig. 13 illustrates a converter of the type shown in Figs. 11 and 12 but provided with solid cooling elements 7 7 in the non-boiling bath in the converter. rlhese solid elements,

which are preferably of high heat conductivity, serve to ell'ect a very uniform heating and in some cases where the non-boiling bath is relatively expensive or relatively heavy, considerable quantities may be used in .order to save bath or to save weight. A marked increase in uniformity and eectiveness is obtained which is desirable for. any exothermic or delicatereactions wh ch can be effectively carried out in converters of this type. Of course, instead of solid elements, elements containing liquids, preferably nonboiling, may be used. lt is also desirable in some cases to use cooling elements placed horizontally instead of vertically or both types ofgelements may be employed wherever suitable.,y The horizontal elements-may also be in the form of, or perform the function of ballles in order toachieve a more uniform flow of non-boiling-'bathover all of the catalyst tubes. llt will be clear, of course that this modification may also be applied to converters such as that 'shown in Fig. 7.

What is claimed as new is: y g 1. A converter comprlsmg 1n combination a plurality of catalyst containing compartments, a normally non-boiling bath liquid at operating temperature surrounding them, heat exchange elements in heat exchanging relation with the bath in contact with such bath and extending'above the level thereof .and means for subjecting the protruding portions of the heat exchange elements to tempering media.

2. A converter according to claim 1 in which at least part of the heat exchange elements consist of compartments partiallyV filled with `liquids which boil at temperatures not far from reaction temperature,'th'e liquid in said compartments extending at least as l far as the upper vsurface ofv the-'non-boiling bath.

8. A converter containing a normally nonboiling bath in which is liquid at operting temperatures, a plurality `of catalyst containf ing compartments in vone portion of said converter and surrounded b v said bath, a portion of said converter remote from thecatalystc'ontaining compartments and separated there, from by baflling means but communicating with the portion of thel converter containing the catalyst compartments at top and bottom, j

the bottom portion of the top communication beingbelow the upper urface of the non-boiling bath, heat exchange elements in heat exchange relation with thewbath' lin the portion of the converter remote from the catalyst containing compartments, said heat exchange elements containing portions out of heat exchange relation with the non-hailing bath, and a liquid having a boilingpoint materially below the operating temperature of the non-boiling bath in the heat exchange elements in heat exchange relation with the non-boiling bath, the ratio of surface of said heat exchange elements to the volume 'of liquid contained therein being sufficiently great so that the liquid boils when the nonboiling bath is at operating temperatures.

nos

normal operating temperatures surrounding said compartments, a portion of the converter separated from the catalyst containing compartments by baliling means but provided with connecting means with the top and bottom of the portion of the converter containing the catalyst compartments, the lowest part of the top connection being below the level of the non-boiling bath, heat exchange elements in said remote portion, 'said heat f exchange elements having a portion in heat exchange relation with the non-boiling bath and a portion out of heat exchange relation therewith.

Signed at Pittsburgh, Pennsylvania, this 16th vday of February, 1928.

ALPHONS 0. JAEGER. 

